1. Field of the Invention
This invention relates to a general purpose array processor and more particularly to an array processor made up of autonomously operating units, including a fixed point and floating point arithmetic unit that is particularly optimized for performing the Fast Fourier Transform algorithm.
2. Prior Art
The problems which are solved by the use of array processors were originally solved by general purpose digital computers. However, because of the complex programming required to perform vector computations, the computing time was far too slow to adequately service real time computer requirements that are required in fields such as seismic data collection.
Special array processors were then designed for use with digital computers. U.S. Pat. No. 4,107,773 describes such a system. In this system, the array processor operates as a direct memory access peripheral device to a general purpose computer to address, fetch, process and store the data arrays in a central memory with a minimum of intervention by the general purpose computer. This type of system was a marked improvement over the general purpose computer for the particular type of computing tasks. However, as the amount of data to be processed has increased, further advances had to be made.
A state-of-the-art type of array processor has a host digital computer that communicates with a centralized controller and a plurality of functional units such as arithmetic units, forming an array processor. The host computer supplies the controller with user instructions. The controller then supplies the functional units with machine language instructions. The controller controls the ordering of operations in the functional units so that the system is limited by the necessary flow of information between the controller and the functional units.
The array processor of this invention eliminates the central controller and provides each functional unit with its own user instructions.